His efforts were to no avail.

他的努力是徒劳的。

《柯林斯英汉双解大词典》

The doctors tried everything to keep him alive but to no avail.

医生千方百计想使他活下来，但无济于事。

《牛津词典》

I pleaded, but to no avail.

我苦苦哀求，但无济于事。

youdao

Mateschitz says his executives meet with French authorities ten times a year--so far to no avail.

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Prime Minister Chuan Leekpai has urged Thais to boycott the casinos, to no avail.

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Venture filed court papers in Germany to stop the insolvency proceedings, to no avail.

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